Locking in poroelasticity

[pereiraICL]

Dear all,

I am having problems with my low-permeability model in ABAQUS using tetrahedrons C3D10MP.

A resulting pore pressure with a checker-board-ish pattern appears.

Is there a way of tackling this permeability locking?

Best,
Andre

 

[JayTung]

Hi Andre,

I encounter the same problem before. That's some kind of numerical oscillation problem. The problem could be your mesh size irregularity. So do finer the mesh and test.

Jay
stungj@gmail.com

 

[pereiraICL]

Jay,

Thanks for your reply.

A considerably finer mesh will still exhibit those problems and I can't afford to refine it further. Using a hexahedral mesh seems to solve it, but it is not the desirable solution either.

Andre

 

[JayTung]

What element type do you use ?
I used to use CPE4. Which did you choose ?

 

[pereiraICL]

I used C3D10MP in the pictured model. I made a hex mesh with C3D8P elements, that apparently solve the problem. Though hex meshes are very hard to develop in organic geometries, so I would like to have a solution that involves tet elements.

Thanks
Andre

 

[JayTung]

I am going to construct a tet element for my model. Let you know if it works well.

Jay